This invention is concerned with window units of the airtight double-hung sash type, such as are being currently installed in homes and particularly in apartment buildings. More particularly, it is concerned with the provision of a vented heading for such units.
The conventional airtight window unit has a pair of sash vertically slidable relative to each other to open and closed positions in side tracks of an encasing frame. When closed, the sashes are airtight to the extent of being sealed against entry of outside fresh air and against escape of inside stale air. Further, the sashes are double glazed. This characteristic, together with the airtight feature serves to create an undesirable aerobic condition within the related apartment. It tends to produce, during any period that the windows remain closed, harmful effects not only upon the interior structure of the apartment but also upon its occupants.
Humidity, condensation and dampness develop in apartments having such window units. This is due to a lack of ventilation through the airtight unit when the sashes remain in a closed condition. Resulting mold growth destroys walls, floors and furniture in the apartment. The humidity and condensation, together with periods of excessive dryness destroys walls, paint and wall paper, warps woodwork and doors, and subjects the occupants of the apartment to sore throats, colds and other discomforts.
Accordingly, a general object of the present invention is to provide the conventional airtight window unit with an improvement which will serve to avoid the harmful effects mentioned and will not materially diminish the general purpose for which such airtight window units are intended.
A more particular object of the invention is to provide a vented heading for an airtight double-hung sash window unit which will provide a desirable exchange of stale room air with fresh outside air.
The invention, together with its various advantages will become increasingly apparent as this specification unfolds in greater detail and as it is read in conjunction with the accompanying drawing, wherein a preferred and specific embodiment of the invention is illustrated.
Briefly, in accordance with the invention an airtight window unit of the double-hung sash type is provided with a heading having vent holes fitted with screened vent plugs. The vent plugs allow a desirable degree of exchange of stale room air with outside fresh air through the heading. Before the outside air flows from the heading to the related room, it is acted upon by a baffle member so that it flows gently into the room without creating undesirable drafts. The baffle member, which is a part of the heading, also serves as decorative interior trim at the room side of the window unit. The screened vent plugs may be varied in number so as to provide a controlled and desirable degree of ventillation to the room.